Bankia SA, the largest Spanish bank due to receive a European bailout, plans to seek buyers for City National Bank early next year in a sale that may fetch at least $500 million, said people with knowledge of the matter.

Bankia has been interviewing U.S. investment bankers seeking to advise on the sale, said the people, who asked not to be named because the matter is private. Bankia may solicit interest from banks interested in expanding in Florida, including BB&T Corp., PNC Financial Services Group Inc., Toronto-Dominion Bank, and BankUnited Inc., one person said.